• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.787-792
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• 2002

The voided slab have many advantages, light weight, high load-distribution capacity, low cost and beautiful appearance, etc. But they have also many cracks due to difficulties in designs and construction, analysis, shrinkage, installation and rising force of voided tube. This paper presents the retrofit effects with steel plate(SP)/carbon fiber sheet(CFS) of RC voided slab. As a results of this study, it proved that the strip pattern has to be profitable than full-face pattern in performance such as crack, ultimate loads, stiffness. Retrofit length has many influence on retrofit effects, as the length increases, performance and stability of end blocks higher. Also, it proved that the retrofit on full-section has to be profitable than voided-section in performance, and the overlay length of CFS is desirable to extent approximately and welding(V-cut) has to be efficient than anchors in SP connection. But the kinds of end block and anchor has not influence on retrofit effects.

• Archives of Plastic Surgery
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• v.47 no.6
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• pp.516-521
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• 2020

In rhinoplasty, osteotomy is becoming more and more frequent as a way to achieve aesthetically pleasing and functional results, as well as patient satisfaction. In procedures to correct a deviated nose, osteotomy to correct the bone plays an essential role in addition to correction of the septum and cartilage, and osteotomy can reduce the wide nose bridge and give a slightly higher appearance in Asian rhinoplasty. However, osteotomy is relatively invasive, and the nasal bones of Asians are often low and thick, so bleeding or swelling during surgery can be somewhat more severe, and a stuffy nose can occur after surgery if osteotomy is performed incorrectly. Since side effects are possible, it is necessary to have a precise understanding of the relevant anatomy and technique. Several articles have described nasal bone osteotomy in rhinoplasty, and this review article introduces the methods presented in various articles, describes indications and limitations, and reviews the relevant anatomical structures and techniques in an accurate manner. We introduce a method that can increase patients' satisfaction and the completeness of surgery through accurate osteotomy, as well as reducing the risk of side effects.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2747-2752
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• 2013

Surface modification of colloidal silica nanoparticles without disrupting the electric double layer of nanoparticles is a major challenge. In the work, silane was employed to modify colloidal silica nanoparticles without inducing bridge flocculation obviously. The effect of pH value of the silica sol, the amount of silane in feed, and reaction temperature on the graft amount and the final size of modified particles was investigated. The increased weight loss by TG and the appearance of $T_2$ and $T_3$ except for $Q_2$ and $Q_3$ signals by CP/MAS $^{29}Si$ NMR of the modified samples verified the successful grafting of silane. The graft amount reached 0.57 mmol/g, which was slightly lower than theory value, and the particle size remained nearly the same as unmodified particles for acidic silica sol at the optimum condition. For alkaline silica sol after modification, aggregates composed of several nanoparticles connected together with silane moleculars as the bridge appeared.

• Journal of the Korean Society for Heat Treatment
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• v.19 no.1
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• pp.30-36
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• 2006

Fretting fatigue behavior of SCM420 steel commonly used in the automotive industry for structural applications was investigated in this study. In addition, the effect of bridge pad on the fretting fatigue test was evaluated from different pad materials and following conclusions were drawn. Simple fatigue limit of SCM 420 steel was determined to be 350 MPa while this value was 225 MPa and 285.5 MPa with SCM420H and with SM45C pad, respectively. Reduction in fatigue limit was, thus found to be 35.7% and 17.9% with SCM 420H pad and SM45C pad, respectively. Results of fracture surface observation revealed that typical striation pattern of fatigue failure existed as well as dimpled and cleavage frature appearance was found in final fractured region. From the EDS compositional analysis, test sample and pad part all had high signals for oxygen and iron, suggesting that worn particles might be iron oxide, although exact chemical composition has to be confirmed. Considerable reduction in fatigue life was apparent in SCM 420 steel under fretting fatigue against simple fatigue. Such reduced fatigue life by fretting damage should be considered as an important factor not only in the viewpoint of repairing but also inevitably in the design stage of structural components.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1174-1187
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• 2007

Monorail System has many advantages compared with other Urban Lightweight Transit Systems, such as the friendliness of the vehicle's appearance, slenderness of the bridge structures, it's low construction cost and short construction period. So, lots of city governments have reviewed or proposed the Monorail System as the attractive alternative system. And recently, Daegu Metropolitan City Government have chosen the Monorail System for the Urban Railroad Line 3. According to these trends on Urban Lightweight Transit Systems, this paper has introduced the outline of the planning and design of Monorail Bridges. At first, trends of overseas Monorail Bridges have been reviewed and the principal design criteria adopted in the basic design of the Urban Railroad Line 3 for Daegu have been introduced. And next, the methods of planning, design, fabrication of the guideway beams which are made of PSC Beam or Steel Beam have been explained. We hope this paper be helpful for the Engineers who are interested in the Monorail Bridges.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.181-187
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• 2005

For 4 years (2000 ${\sim}$ 2003), annual fluctuations of standing crops of cyanobacteria and physicochemical factors were examined at five sites from Bridge of Seungsoo to Bridge of Seungsan in the lower part of Han River. The cyanobacterial abundance (ND to 4,167 cells $mL^{-1}$) was strongly decreased during the heavy rains in every year. During the similar periods in 2003, cyanobacteria hardly observed, and comprised below of 10 percentage of total phytoplankton. In the period of little cyanobacteria, some green algae and diatom dominated the phytoplankton community, while the concentration of chlorophyll a has not largely change. These results indicate that heavy frequent precipitation strongly limited the growth of cyanobacteria, and lead an algal succession by the appearance of new algal groups.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.59-66
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• 2019

Small bridges carry out only general inspections based on visual inspection. The Bridges with more than 30 years of public use need to be decided on whether or not they will be reconstruction according to aging. However, there are some situations that need to be determined only by appearance condition, which is insufficient in terms of safety maintenance. In this paper, the condition evaluation and the load carrying capacity evaluation were carried out for aged small bridges. A comparison of the evaluation results was conducted to examine the appropriateness of the maintenance related to the decision making of the reconstruction. As a result of reviewing, two of the bridges showed that there are no abnormality in the safety of the state evaluation, but the load capacity were insufficient. Thus evaluation the safety and performing the reconstruction decision of aged small bridges by visual inspection alone with may cause problems. Therefore, it is necessary to carry out additional research on the ambient measurement and load carrying capacity evaluation for the maintenance of the bridges, and to supplement it through application of the bridge management system.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.2
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• pp.121-128
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• 2005

This study focuses on evaluating the reliability index of a deck of RC slab having chloride contamination and studying the relation of grades of rebar corrosion and the reliability index of a bridge deck For this purpose, first, the failure probability related to flexural strength was calculated using a model for deterioration, which contains the application of deicing salts that usually causes significant long-term deterioration and reduction in the structural safety for strength of structure. And also, according to the depth of covering, the chloride contents depending on time due to depths of RC slab deck, the appearance time for initial corrosion of rebar and the occurrence time for split of covering were investigated using a MCS method.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.4 no.1
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• pp.12-16
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• 2008

Williams syndrome is a rare genetic disorder with a frequency of one per 20,000~50,000 live births. It is caused by a deletion of one elastin allele located within chromosome subunit 7q11.23(long arm). This syndrome is frequently accompanied by disorders such as congenital heart disease, facial anomalies, mental retardation, and so on. The characteristic facial appearance includes full lips, rounded cheeks, broad forehead, periorbital fullness, flattened bridge of nose, small nose with anteverted nostril, long filtrum and low-set ears. In oral features, hypodontia, high prevalence of dental caries, microdontia, enamel hypoplasia, delayed eruption, and malocclusions have been found. Most adult patients with Williams syndrome lack social adaptability and lead seclusive lives, however, young patients are rather very friendly and talkative, and seem smarter than their actual intellectual quotients. They also tend to favor staying with grown-ups rather than mixing with their peers, and tend to present problematic temper tantrum during dental treatment.

• Journal of the Korea Society of Computer and Information
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• v.15 no.11
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• pp.109-116
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• 2010

This study is intended to propose a technique that can trace objects by utilizing the multimarker method in the Marker Recognition which is a bridge way connecting virtuality and reality in complex environments or in a condition hands become obstacles. In the existing marker method, the object becomes blinking when the maker is blocked since this method relies only on single marker. However, the researcher was able to confirm the appearance of augmented object when the marker was blocked for the multiple markers replaced the blocked one. In order to implement such technique, multi-marker estimation was utilized with perspective matrix. The advantage is the fast estimation process for there is no need of other calculation. The implemented technique can detect markers and locate their positions, represent 3-D object in various circumstances.